提供程序io.swagger.scala.converter.SwaggerScalaModelConverter无法实例化 [英] Provider io.swagger.scala.converter.SwaggerScalaModelConverter could not be instantiated

问题描述

在尝试将招摇入我的API时，我遇到了一些问题.

When trying to incorporate swagger into my API I'm running into some issues.

我的API使用的是Jersey 2.22，语言是Scala.我在pom中添加了以下依赖项:

My API is using Jersey 2.22 and the language is Scala. I've added the following dependencies to my pom:

<dependency>
    <groupId>io.swagger</groupId>
    <artifactId>swagger-annotations</artifactId>
    <version>1.5.12</version>
</dependency>

<dependency>
    <groupId>io.swagger</groupId>
    <artifactId>swagger-scala-module_2.11</artifactId>
    <version>1.0.3</version>
</dependency> 

我的插件配置如下:

<plugin>
    <groupId>com.github.kongchen</groupId>
    <artifactId>swagger-maven-plugin</artifactId>
    <version>${kongchen.plugin.version}</version>
    <executions>
        <execution>
            <phase>compile</phase>
            <goals>
                <goal>generate</goal>
            </goals>
        </execution>
    </executions>
    <configuration>
        <apiSources>
            <apiSource>
                <locations>${swagger.locations}</locations>
                <springmvc>false</springmvc>
                <host>${swagger.host}</host>
                <basePath>${base.path}</basePath>
                <info>
                    <title>${swagger.title}</title>
                    <version>${project.version}</version>
                    <description>${swagger.description}</description>
                </info>
                <swaggerDirectory>${project.build.directory}/</swaggerDirectory>
                <outputFormats>yaml,json</outputFormats>
            </apiSource>
        </apiSources>
    </configuration>
</plugin>

当我运行mvn编译时，会发生以下错误:

When I'm running mvn compile, the following error occurs:

Exception in thread "main" java.util.ServiceConfigurationError: io.swagger.converter.ModelConverter: Provider io.swagger.scala.converter.SwaggerScalaModelConverter could not be instantiated
        at java.util.ServiceLoader.fail(ServiceLoader.java:232)
        at java.util.ServiceLoader.access$100(ServiceLoader.java:185)
        at java.util.ServiceLoader$LazyIterator.nextService(ServiceLoader.java:384)
        at java.util.ServiceLoader$LazyIterator.next(ServiceLoader.java:404)
        at java.util.ServiceLoader$1.next(ServiceLoader.java:480)
        at io.swagger.converter.ModelConverters.<clinit>(ModelConverters.java:114)
        at com.github.kongchen.swagger.docgen.AbstractDocumentSource.loadModelModifier(AbstractDocumentSource.java:179)
        at com.github.kongchen.swagger.docgen.mavenplugin.ApiDocumentMojo.execute(ApiDocumentMojo.java:71)
        at org.apache.maven.plugin.DefaultBuildPluginManager.executeMojo(DefaultBuildPluginManager.java:134)
        at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:207)
        at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:153)
        at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:145)
        at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject(LifecycleModuleBuilder.java:116)
        at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject(LifecycleModuleBuilder.java:80)
        at org.apache.maven.lifecycle.internal.builder.singlethreaded.SingleThreadedBuilder.build(SingleThreadedBuilder.java:51)
        at org.apache.maven.lifecycle.internal.LifecycleStarter.execute(LifecycleStarter.java:128)
        at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:307)
        at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:193)
        at org.apache.maven.DefaultMaven.execute(DefaultMaven.java:106)
        at org.apache.maven.cli.MavenCli.execute(MavenCli.java:863)
        at org.apache.maven.cli.MavenCli.doMain(MavenCli.java:288)
        at org.apache.maven.cli.MavenCli.main(MavenCli.java:199)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.lang.reflect.Method.invoke(Method.java:497)
        at org.codehaus.plexus.classworlds.launcher.Launcher.launchEnhanced(Launcher.java:289)
        at org.codehaus.plexus.classworlds.launcher.Launcher.launch(Launcher.java:229)
        at org.codehaus.plexus.classworlds.launcher.Launcher.mainWithExitCode(Launcher.java:415)
        at org.codehaus.plexus.classworlds.launcher.Launcher.main(Launcher.java:356)
Caused by: java.lang.VerifyError: Cannot inherit from final class

如果我遗漏了scala-swagger模块，则编译工作正常，并且我得到了一个有效的json(所有资源描述均完美生成)，但是scala case类中的字段未生成:

If I leave out the scala-swagger module, compile works fine and I'm getting a valid json (all resource descriptions are generated perfectly), but the fields in the scala case classes don't get generated:

@ApiModel("some model")
case class HelloModel(@(ApiModelProperty @field)(dataType = "Int", value = "some int", name = "tries") tries: Int)

结果:

"definitions" : {
    "some model" : {
      "type" : "object"
    }
  }

有人知道吗?

推荐答案

好吧，我在经过大量调试之后才弄清楚了.看来我正在使用(3.1.1)的swagger-maven-plugin使用的是swagger-core 1.5.4.这种招摇的核心依赖项依赖于Jackson 2.4.5.

Well I figured it out after some heavy debugging. It appears the swagger-maven-plugin which I was using (3.1.1) was using swagger-core 1.5.4. This swagger-core dependency had a dependency to Jackson 2.4.5.

swagger-scala-module_2.11使用的是Jackson 2.8.7. 无法从最终类继承"错误来自TypeReference类，该类显然已更改/获得了2.8.7的引入.

The swagger-scala-module_2.11 is using Jackson 2.8.7. The "Cannot inherit from final class" error came from the TypeReference class, which apparently changed/got introduced in 2.8.7.

解决方案是通过使用依赖性块将swagger-scala-module_2.11包含在swagger-maven-plugin内:

The solution was including the swagger-scala-module_2.11 inside of the swagger-maven-plugin by using the dependencies block:

<build>
    <plugins>
        <plugin>
            <groupId>com.github.kongchen</groupId>
            <artifactId>swagger-maven-plugin</artifactId>
            <version>${swagger-scala-maven-plugin}</version>
            <executions>
                <execution>
                    <phase>compile</phase>
                    <goals>
                        <goal>generate</goal>
                    </goals>
                </execution>
            </executions>
            <dependencies>
                <dependency>
                    <groupId>io.swagger</groupId>
                    <artifactId>swagger-scala-module_2.11</artifactId>
                    <version>1.0.3</version>
                </dependency>
            </dependencies>
            <configuration>
                <apiSources>
                    <apiSource>
                        <locations>
                            <location>${swagger.locations}</location>
                        </locations>
                        <springmvc>false</springmvc>
                        <host>${swagger.host}</host>
                        <basePath>${base.path}</basePath>
                        <info>
                            <title>${swagger.title}</title>
                            <version>${project.version}</version>
                            <description>${swagger.description}</description>
                        </info>
                        <swaggerDirectory>${project.build.directory}/</swaggerDirectory>
                        <outputFormats>json</outputFormats>
                    </apiSource>
                </apiSources>
            </configuration>
        </plugin>
    </plugins>
</build>

这将使swagger-maven-plugin使用swagger核心1.5.12而不是所提供的1.5.9.

This will make the swagger-maven-plugin use swagger core 1.5.12 instead of the provided 1.5.9.

这篇关于提供程序io.swagger.scala.converter.SwaggerScalaModelConverter无法实例化的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！